Tools
Geometry calculator
Drag triangles, angles, and the plane — geometry you can feel.
Overview
The theorem is an area relationship. Drawing squares on each side and dragging the legs is more convincing than memorizing a² + b² = c² alone.
Classroom example
Start from a 3-4-5 triple, then morph continuously — numbers change, the equality holds — to build “identity” intuition.
Resources in this tool
FAQ
Can this replace a formal proof?
Use it to motivate the geometric meaning and verify; follow with a formal proof from your curriculum.
Must the triangle be right-angled?
Yes. The theorem holds for right triangles only; c is the hypotenuse.
How does this connect to similarity?
Similarity inside a right triangle can also yield Pythagoras — open the similar-triangles tool next.
How do I write a² + b² = c² afterward?
Use the equation editor or the Geometry pillar to copy a clean expression into notes.